MongoDB vs X Interview Questions
MongoDB lists 24 LeetCode interview questions while X lists 51. They share 5 problems — 21% of MongoDB's bank and 10% of X's. Focus on the overlap first, then drill into 19 MongoDB-only and 46 X-only questions.
Overview
Preparation Strategy
Step 1 — Shared core: Solve the 5 overlapping problems first. These are the highest-yield questions for candidates interviewing at both MongoDB and X.
Step 2 — Company-specific depth: Add MongoDB-specific problems like Word Break, Snapshot Array, Intersection of Two Arrays and X-specific problems from the exclusive lists below.
Step 3 — Difficulty tuning: MongoDB skews harder in our data. Budget extra time for Hard problems if you are targeting that company.
Difficulty Comparison
Top Shared Topics
5 Shared Questions
High-priority problems to practice for both MongoDB and X.
| Problem | Difficulty |
|---|---|
| Implement Trie (Prefix Tree) | Medium |
| Merge k Sorted Lists | Hard |
| LRU Cache | Medium |
| Merge Intervals | Medium |
| Word Break II | Hard |
Unique to MongoDB (19)
Problems in MongoDB's list that do not appear at X.
| Problem | Difficulty |
|---|---|
| Word Break | Medium |
| Snapshot Array | Medium |
| Intersection of Two Arrays | Easy |
| Text Justification | Hard |
| Convert JSON String to Object | Hard |
| Insert Interval | Medium |
| Web Crawler Multithreaded | Medium |
| Stock Price Fluctuation | Medium |
| Course Schedule II | Medium |
| Merge Two Binary Trees | Easy |
| Sliding Window Maximum | Hard |
| Lowest Common Ancestor of a Binary Tree | Medium |
Unique to X (46)
Problems in X's list that do not appear at MongoDB.
| Problem | Difficulty |
|---|---|
| Trapping Rain Water | Hard |
| Tweet Counts Per Frequency | Medium |
| Flatten Nested List Iterator | Medium |
| Insert Delete GetRandom O(1) | Medium |
| Design Twitter | Medium |
| Binary Gap | Easy |
| Regular Expression Matching | Hard |
| Integer to Roman | Medium |
| Alien Dictionary | Hard |
| Time Needed to Buy Tickets | Easy |
| Valid Parentheses | Easy |
| Max Points on a Line | Hard |
Frequently Asked Questions
How many LeetCode questions do MongoDB and X share?
MongoDB and X share 5 LeetCode interview questions. 19 problems appear only in MongoDB's list and 46 appear only in X's list.
What topics overlap most between MongoDB and X?
The most common shared topics between MongoDB and X are Hash Table (3 shared questions), String (2 shared questions), Design (2 shared questions), Trie (2 shared questions), Linked List (2 shared questions). Mastering these areas prepares you for both companies.
Which company asks harder LeetCode questions: MongoDB or X?
MongoDB has 3 Easy, 15 Medium, and 6 Hard questions. X has 8 Easy, 31 Medium, and 12 Hard questions. MongoDB has a higher proportion of Hard problems in its interview set.
How should I prepare if interviewing at both MongoDB and X?
Start with the 5 shared problems since they cover what both companies ask most often. Then add 19 MongoDB-specific and 20 X-specific questions to round out your prep.